Warm Up 4/9

Write the formula of magnesium chloride.

Hint: Mg has a charge of +2. Cl has a charge of -1.

Gas Laws

Lesson: Kinetic Molecular

Theory

Solids/Liquids/GasesDescribe the molecules in the

following images.

http://www.google.com/url?sa=i&rct=j&q=oxygen+tanks+&source=images&cd=&cad=rja&docid=5gIYxydZ5So9tM&tbnid=cg5W8oaKezzYSM:&ved=0CAUQjRw&url=http://www.caregiverproducts.com/e-size-walker-oxygen-tank-holder.html&ei=J1BjUeXjIZLM9gTMuYHYBw&bvm=bv.44770516,d.eWU&psig=AFQjCNEFJn1H5XPMR0SWP8VTu_JlhfV4wA&ust=1365549344495056

http://www.google.com/url?sa=i&rct=j&q=propane+grill&source=images&cd=&cad=rja&docid=k5iRxAyF1N_bBM&tbnid=zSROs_KJ_uiO9M:&ved=0CAUQjRw&url=http://blogs.rrc.state.tx.us/TPF/?p=2715&ei=YFBjUdCGLIOC8ASuvoGoBQ&bvm=bv.44770516,d.eWU&psig=AFQjCNGIG-L74OcVkXkvTBf-N6CZo2ji5A&ust=1365549510160817

http://www.google.com/url?sa=i&rct=j&q=paintball+gun+shooting&source=images&cd=&cad=rja&docid=msOvkt2l7UwEuM&tbnid=IUXWaMZBtHKEHM:&ved=0CAUQjRw&url=http://www.visualphotos.com/image/2x4160223/man_shooting_paintball_gun&ei=_VBjUZTHFIfu9ASDiYGwCA&bvm=bv.44770516,d.eWU&psig=AFQjCNFis0tJiIHxI9iweOFthNrruRNFbw&ust=1365549617200611

http://www.google.com/url?sa=i&rct=j&q=gas+stove&source=images&cd=&cad=rja&docid=r7J8gGDyHTSv9M&tbnid=wF033qNE8KWlYM:&ved=0CAUQjRw&url=http://www.brynninbrazil.com/stove-top-terror&ei=L1FjUZXTD4rK9QSk0oDoCQ&bvm=bv.44770516,d.eWU&psig=AFQjCNHOBUZ3Rs3b_Z8T-WLqJw-hCUoXog&ust=1365549736008447

http://www.google.com/url?sa=i&rct=j&q=cartoon+fart&source=images&cd=&cad=rja&docid=oy1oeHe6OdCEPM&tbnid=2X1aSr6M4ZDdKM:&ved=0CAUQjRw&url=http://meme-pictures.feedio.net/fart-cloud-cartoon-pictures/&ei=qFFjUaDVHZKC8QSxloHoBQ&bvm=bv.44770516,d.eWU&psig=AFQjCNFbhK-kpqr7peiaUpqiI18VenCuKg&ust=1365549791012888

Kinetic Molecular TheoryA model that assumes that an ideal

gas is composed of tiny particles (molecules) in constant motion.

Ideal Gas- an imaginary gas that

perfectly fits all of the KMT.

5 Parts of KMT:

1. Matter is composed of very small

particles called molecules.

2. Molecules are in constant motion.

The collisions with the walls of the

container cause pressure.

Continued3. When the molecules collide with

each other or the walls of a

container, there is no loss of energy

(elastic collision).

4. There are no forces of attraction

or repulsion between gas particles,

but they collide and change

direction.

5. The average kinetic energy of gas

particles depends on the temperature

of the gas.

Temperature- measure of the

average kinetic energy of

particles.

Pressure Units Standard atmosphere (atm)

1 atm= 760 mm Hg = 760 torr

Pascal- SI unit for measuring

pressure:

1 atm= 101300 Pa = 101.3 Kpa

Draw a picture for each of

the parts of the KMT.

Warm Up

If an atom has a charge of -2, has it been oxidized or

reduced?

Lesson: Gas Laws

(Part 1)

Gas Laws

Gas laws express the behaviors of gases as

mathematical relationships.

Boyle's Law-Pressure and volume

-States that the pressure and volume of

a gas are inversely proportional to

each other at constant temperature.

Boyle's Law

Formula:

P1*V1 = P2*V2

P1= initial Pressure P2= final

pressure

V1= initial volume V2= final volume

A gas has a volume of 1.25 L and a pressure of 755 torr. What will the new volume be if the pressure is increased to 2667.6 torr?

Boyle’s Law Example

Charles' Law-Volume and temperature

-The volume of a gas is directly

proportional to the temperature

at constant pressure.

Charles' Law

Formula:

V1= initial volume V2= final volume

T1= initial temperature T2= final

temperature

**Temperature must be in Kelvin!

V1 V

2

T1 T

2

=

If a gas has a volume of 247 mL at 25.0°C, what will the new volume be if the temperature is increased to 308°C?

Charles’s Law Example 1

If a gas has a volume of 247 mL at 25.0°C, what will the new temperature be if the volume is increased to 255 mL?

Charles’s Law Example 2

Ideal Gas Law

P= pressure (in atm)

V = volume (in Liters)

n = number of moles

R = universal gas constant

T = temperature (Kelvin)

-

Formula: PV = nRT

Universal Gas Constant (R)

-value can vary depending on

pressure units being used.

R= 0.0821 L·atm mol·K

Example #1 (Ideal Gas Law)What is the pressure of 5 moles

of a gas at 30°C in a 2 liter container?P x 2 L = 5 mols x 0.0821 x 303 K

2 L 2 L

P = 60 atm

Example #2 (Ideal Gas Law)A 250 mL of a gas exerts a pressure

of 760 torr at 10°C. How many moles of gas are present?1 atm x 0.250 L = n x 0.0821 x 283 K

0.0821 x 283 K

n = 0.0108 mol

(0.0821 x 283 K)

7) If I have 4 moles of a gas at a pressure of 5.6 atm and a volume of 12 liters, what is the temperature?

8) If I have an unknown quantity of a gas at a pressure of 1.2 atm, a volume of 31 liters and a temperature of 87°C, how many moles of gas do I have?

9) If I put 3 moles of gas in a container with a volume of 60 liters and at a temperature of 400 K, what is the pressure inside the container.

10) If I have 7.7 moles of a gas at a pressure of 0.09 atm and a temperature of 56°C, what is the volume of gas?

Get your notebooks!

You will find your score near the last page.

AgNO3 (aq) + KCl (aq) → AgCl (s) + KNO3 (aq)

What type of reaction?

What type of reaction?

2NaOH + H2SO4 → 2H2O + Na2SO4

2Mg + O2 → 2MgO

What type of reaction?

http://www.google.com/url?sa=i&rct=j&q=periodic+table&source=images&cd=&cad=rja&docid=umydHKgNw-dNmM&tbnid=TcBEsccJRIeL_M:&ved=&url=http://chemistry.about.com/od/periodictableelements/a/printperiodic.htm&ei=BwdoUcLnAdHxqQGkh4CoCw&bvm=bv.45175338,d.aWM&psig=AFQjCNHrC_pLGjCwzm_eTA7T4XblpquVVg&ust=1365858439239386

Write the ionic formula of the following ions:

Na O

What is the following temperature in Kelvin?

20°C

How many torr are in 2 atm?

What is the ideal gas formula?

What is instrument is used to measure atmospheric gas

pressure?

Lesson: Gas Laws

(Part 2)

Dalton's Law of Partial Pressures-states that the pressure of a gas mixture is

the sum of the partial pressures of the individual components of the gas mixture.

Formula: Ptotal

= P1+P

2+P

3+...

Example (Partial Pressure)A mixture of oxygen, hydrogen and nitrogen

gases exerts a total pressure of 278 kPa. If the partial pressures of the oxygen and the hydrogen are 112 kPa and 101 kPa respectively, what would be the partial pressure exerted by the nitrogen?

Avogadro’s Law-Volume and number of moles

-States that the volume and # of moles

of a gas are directly proportional to

each other at constant temperature

and pressure.

Avogadro’s Law

Also means: Equal volumes of 2 gases at the same temperature and pressure have equal numbers of moles.

STP = Standard Temperature and Pressure (0°C, 1 atm)

1 mole of gas = 22.4 L at STP

Avogadro‘s Law

Formula:

V1= initial volume V2= final volume

n1= initial # of moles n2= final # of moles

Example

Mass: 0.214 mol Mass: 0.375Volume: 652 mL Volume: ?

ExampleCalculate the volume that .881 mol

of gas at standard temperature and pressure will occupy.

1. If a mixture of oxygen gas and water vapor have a total pressure of 754 torr, and the water vapor has a partial pressure of 21 torr, what is the partial pressure of the oxygen?

2.Mass: 46.2 g O Mass: 5.00 g OVolume: 100. L Volume: ?

Hint: the mass needs to be in moles, so look up the molar mass and use a molar mass conversion fact to calculate the # of moles.

Left Side Practice

Behavior of Gases

1. Gases can expand

2. Gases can be

compressed

** Expansion and compression are affected by temperature and pressure.

Temperature Measure of the average kinetic energy

Kinetic Energy = 1/2 mv2

Units: Fahrenheit (°F), Celsius (°C), and Kelvin (K)

Kelvin (K): directly relates temperature to kinetic energy

Absolute Zero: 0K, temperature where motion stops

Converting temperature

Celsius to Kelvin

TKelvin = TCelsius + 273

Kelvin to Celsius

TCelsius = TKelvin -273

PracticeConvert the following temperatures to Kelvin or Celsius.

1. 15°C

2. 100 K

3. 125°C

4. 0 K

5. 722 K

6. –100°C

Pressure

Pressure- force per unit of area

Gas pressure- the force exerted upon a container by a gas; caused by gas particles striking the sides of the container.

Standard Temperature and Pressure

*Standard set of experimental conditions used to make comparison of data easier.

At STP: T= 0°C and P= 1 atmosphere